Once the couscous has completed its second steaming, empty it into your large bowl again. Break it apart, and allow to cool slightly.
Separately add 2 1/2 to 3 cups of water, tossing and mixing the couscous with your hands after each addition. The couscous is now quite light and fluffy, and should lean toward al dente when you try it. It will continue to tenderize during the last steaming and from adding broth during serving time.
Transfer the couscous to the steamer – remember not to compress the couscous, just pile it in lightly – and steam for the final time for another 10 to 15 minutes, timing from when you see the steam. Again, seal the joint of the couscoussier if necessary.
Due to the volume of couscous, it will take a bit longer to see the steam emerge. Because of this, some Moroccan cooks don't add all the couscous for the final steaming in a single quantity. They might place one-third or one-half of the couscous in the steamer, and add more when they see the steam rising.
